Well, Laura may have a different answer but I think it would be a shame not to finish the trilogy with 'Tempting Harriot.' I'm about half way through and it provides more interesting angles to the overall dynamic of the two previous.
I think it would be good to stick to the stories I've vetted. Remember, there are quite a few books, even by the authors I have named, that I have NOT recommended because the themes are not what I would consider wholesome for our purposes here (Tempt the Devil being one of those). There's already a huge selection. And it doesn't hurt to finish one series by one author, and then read another series by another author, and then switch back. And since they are all on kindle, it's pretty cheap.